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[80.230.68.31]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47aa039b126sm32286020f8f.24.2026.07.07.03.25.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Jul 2026 03:25:40 -0700 (PDT) Date: Tue, 7 Jul 2026 06:25:36 -0400 From: "Michael S. Tsirkin" To: "David Hildenbrand (Arm)" Cc: Sourav Panda , muchun.song@linux.dev, osalvador@suse.de, akpm@linux-foundation.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, mhklinux@outlook.com, fvdl@google.com, gthelen@google.com, mike.kravetz@oracle.com, pasha.tatashin@soleen.com, rientjes@google.com, riel@surriel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [RFC PATCH 0/6] mm/hugetlb: Dynamic, NUMA-aware HugePage Cache & Free Page Reporting Message-ID: <20260707062428-mutt-send-email-mst@kernel.org> References: <20260707064235.1386552-1-souravpanda@google.com> <9624988a-366e-4884-9408-3f3b88c27290@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9624988a-366e-4884-9408-3f3b88c27290@kernel.org> On Tue, Jul 07, 2026 at 09:29:07AM +0200, David Hildenbrand (Arm) wrote: > On 7/7/26 08:42, Sourav Panda wrote: > > Overview > > This patch series introduces a dynamic, NUMA-aware HugePage Cache, > > backed by a kernel shrinker to safely return memory under pressure, and > > integrates it with Free Page Reporting (virtio-balloon) for HugeTLB, > > specifically targeting gigantic (1GB) hugepages. The goal is to solve > > the tradeoff between allocation latency and memory > > fungibility in virtualized and heterogeneous cloud environments. > > Hi, > > in general, we consider hugetlb nowadays to be mostly in feature freeze, as we > realized a while ago that adding more special casing on top of something too > special for all of MM is only going to hurt us more in the long run. > > We want to have less special casing and less special sauce, not more. > > Now, there is nothing wrong in making hugetlb be less special, by making it use > more of core infrastructure etc. > > But optimizing for surplus hugetlb pages by teaching hugetlb about new caches > and its custom free-page-reporting support rather looks like the wrong direction > for me? > > -- > Cheers, > > David It is currently bypassing free-page-reporting completely. Making existing free lists not ignore free-page-reporting would maybe considered "making it be less special"?